K7LXC@aol.com wrote:
>
> > The bigger question is - why are you putting up a big Mosley antenna?
> > Have you already purchased it or are contemplating it?Just about any other
> > antenna out there will be a better performer.
>
> I've had several inquiries into my comment on Mosley antennas. As you
> could tell, I'm not a big fan of them. My opinion is that they don't work very
> well. Good SWR? Yes. Robust construction? Sure. Performance? Not that great.
>
> I install ham towers and antennas professionally and I've worked on over
> 100 different stations. I have also received email from and talked to hundreds
> of people about antennas (including recognized experts in the ham antenna
> field) and have used some of them myself.
>
> There are two types of Mosley owners. The first is the one that feels like
> it's a pretty good antenna. I think there are 2 reasons for this. First is
> that they don't have another antenna to compare it to (like a dipole or other
> yagi and not a trapped vertical) so when they work something, it must be
> working FB. The second reason is a justification that something that big and
> that expensive must work.
>
> The second type of Mosley owner is the one who has used it, found its
> deficiencies and will make you a heckuva deal on a slightly used one! There
> are a couple here in the Seattle area that would like to talk to you if you're
> interested in buying one.
>
> I guess the clincher for me as a contester is that there are darn few
> competitive stations that use them. There are no stacks of Mosleys at ANY
> serious contest station unlike TH7's, KT34XA's or even C-3's. These stations
> don't even have ONE Mosley at their station. Why not? THEY DON'T WORK!
>
> Okay, Steve, that's nice hyperbole but do you have any empirical data to
> back up your claims? Funny you should ask. N0AX and myself have run field
> tests on a couple of multiband antennas. These tests were conducted under
> controlled conditions and used a reference dipole at the same height so the
> figures are dBd. Here's what we found with a PRO77:
>
> 14.025 0.0 gain dBd
> 14.100 1.0
> 14.175 1.0
> 14.250 -0.5
> 14.325 1.0
>
> 21.025 4.0
> 21.125 4.0
> 21.225 4.0
> 21.325 3.0
> 21.425 0.5
>
> 28.050 -3.0
> 28.250 -1.5
> 28.450 -1.5
> 28.650 -1.5
> 28.850 -2.0
>
> Yes, there are some negative gain figures. Doesn't look like the catalog
> figures at all, does it? I submit that these are "typical" Mosley figures
> since most all of the antennas use the same trap and element configurations.
>
> Here are the measurements for the KT34XA:
>
> 14.025 4.0 dBd
> 14.100 4.0
> 14.175 4.0
> 14.250 3.5
> 14.325 -2.5
>
> 21.025 6.0
> 21.125 4.5
> 21.225 1.5
> 21.325 0
> 21.425 -1.5
>
> 28.050 4.0
> 28.250 5.0
> 28.450 5.0
> 28.650 5.0
> 28.850 3.5
>
> These are reproduceable results that have been confirmed with other
> similar tests.
>
> Before you get too excited, as of right now we will be presenting this
> information at the DX Convention in Visalia and the Antenna Forum at Dayton.
> The information is NOT available until then (we've got a couple more antennas
> to test and then we need to finish the paper) so don't ask. It will be
> available when it's done.
>
> 73, Steve K7LXC
>
> TOWER TECH -- professional tower supplies and services for amateurs
>
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Well now, Let me add my two bits! 2 years ago I
bought the Mosley PRO67. I really like the idea
of having so many bands on one antenna. So
up it went to 90 Feet! After it was up, boy was I
impressed with the low SWR. Then I started using
it. No matter which direction I pointed it the
received signal strength was the same! What
happened to the front to back ratio. There was no
difference. Anyway, all of the elements are down
now and hanging it a tree as a storage place.
This all happened after Stan W7NI told me about
what other amateurs had to say about this
particular antenna off of the reflector here.
I sure wouldn't want to discourage you from buying
a Mosley. However, as far as I am concerned, I
won't buy again from them. I plan to put up a
mono bander on 20 and dual band 10-15 on a side
mount. Sure wish I had been on the internet
before I bought mine. Anyone want a free PRO-67
Mosley?
Best regards,
John K7JB
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